We need hemp - lots of it - for cordage, but hemp means marijuana,
too. Can scientists take the drug menace out of this useful plant?

Co-operating with the U.S. Department of Agriculture, American
farmers will produce 75,000 tons of hemp fiber this year, and
probably more than twice as much in 1944. The record-shattering
crops will replace Manila fiber from the Philippines and sisal
from the Dutch East Indies, which are now cut off by the war.

The result will be a boon to users of cordage - and a headache
for law-enforcement officers. A Jekyll-and-Hyde plant, hemp provides
twine and rope urgently needed for military purposes. But it also
yields marijuana, a drug that makes depraved creatures of its
addicts. What can be done to keep these enormous new supplies,
from which there almost inevitably will be "leaks,"
out of their twitching hands?

"Drugless hemp" is the bold proposal of the Department
of Agriculture for solving the problem. In short, it is attempting
to breed a strain of hemp of good fiber quality, but containing
a negligible amount of the baneful marijuana drug. For aid, it
has enlisted the expert services of Dr. H.E. Warmke, at the Cold
Springs Harbor, N.Y., experimental station of the Carnegie Institution.

First of Dr. Warmke's problems has been to develop a method
of determining reliably the amount of marijuana in individual
hemp plants. With undesirables weeded out, he then cross-pollinates
and breeds the desirable, or relatively drug-free, plants. Only
a little more time will be needed to learn whether he can establish
a pure, self-perpetuating race of them.

Fish serve as test animals for determining the potency of marijuana
extracts. Previous experimenters have used dogs, and tried to
estimate the extent of their marijuana "jag" - something
hard to reduce to cold figures. But when a fish is placed in a
strong solution of marijuana extract, it soon is most thoroughly
dead, and such an observation cannot be disputed. Therefore, Dr.
Warmke puts two killifish, or "Atlantic minnows," into
each of four beakers containing precisely measured dilutions of
the drug - very strong, strong, medium, and weak. Then he can
record the number of fish killed and get a definite measure of
the poison in the plant.

First encouraging results show a great range in the amount
of marijuana in different hemp plants. Some prove to be one eighth
as poisonous as others an excellent starting point for a plant
breeder. And actual breeding has definitely resulted in improvement.
With true scientific caution, Dr. Warmke refuses to admit having
"Burbanked" a drugless hemp until a few more plant generations
have been tested, but to a layman's eyes he seems close to his
goal.

[Photograph captions]

This year America will grow 75,000 tons of hemp fiber whose
leaves and flowers (left) will contain marijuana. (Photograph
Above from U.S. Department of Agriculture)

1 The seedling of one of many plants being bred to reduce the
marijuana content of hemp

2 Dried center leaflets from each leaf of mature plant are
ground to powder in mortar

3 Measured amount of powder is put in vial, and a chemical
is added to extract marijuana

4 To determine the potency of the extract, a pair of killifish
are placed in each of four beakers containing solutions of the
drug ranging from very strong (left) to weak (right). In this
way, the number of fish that are killed gives a graduated measure
of the amount of marijuana in the plant tested.

5 In effort to breed a "pure" hemp, plants with low
toxicity are cross-pollinated by shaking pollen from male plant
(right) on stigmas of female